Alt-BEAM Archive

Message #11859



To: beam@corp.sgi.com
From: Justin JAF60@student.canterbury.ac.nz
Date: Wed, 15 Mar 2000 19:08:37 +1300
Subject: [alt-beam] Re: Miniature video transmitter?


>Given the wieght and size of the CCD and any transmittion equipment
>(probably kits are available) you would
>need to mount this on a walker, probably a stryder since those can
>carry a bigger load.

No, I've seen transmitters small enough that you could load them and the
CCD onto a photopopper. You'd have to put the solar panel on top of
them, but the level of miniaturisation does exist and I think kits were
sold, just too expensive for me (circumstances would also suggest that
the expense was largely for R&D and profit, rather than component
costs). Anyway, the point of this message is to say that it _is_
possible, we just need to find out how :-)



11860 Wed, 15 Mar 2000 19:08:40 +1300 [alt-beam] Re: Vibration sensor from Silly Slammer beam@corp.sgi.com Justin >There were some kits for key chain size devices to store any sound &
>play it back for 20 second duration. These will allow you to record
>anything that you want your robot to say. The price was about $ 20. I
>think I have also seen somewhat expensive pens with a recording chip
>like this.

There are also the Yak-Back toys. They're resonably small, cost
about US$10 and record for 8 seconds. There are more advanced versions
with extra stuff like effects filter buttons for around $15 I think.
I've got one of the basic ones, the sound quality is poor. The circuit
is quite small, it runs on 6V but draws very little current when
activated, and requires no current to store the recorded sound.



11861 Wed, 15 Mar 2000 19:08:42 +1300 [alt-beam] Re: Minit motors beam@corp.sgi.com Justin >These are LEGO parts? Are they in the standard catalogs?

There are two catalogues (though often you get both - one attached
inside the other). The normal catalogue is of the year's lego sets, the
second one is the "Lego Service" catalogue, and this is of the
individual parts that you can mail-order, or buy from Lego "superstores"
(a lego retailer that stocks these supplement bags :). These
"supplementary LEGO element packets" are important lego parts but are
useless in themselves (ie their purpose is replacement parts if your kid
loses a crucial part of their lego set), and the catalogue is
international (the one I have has the prices in 17 different countries,
and mail-order details for same. Canada and the USA are not among them,
so they'll have their own catalogue).

> >I'm looking into it, and believe it or not, some of the best looking
> >stuff I've seen is some lego parts. Lego isn't cheap, but it's an
> >unlimited supply of parts that are available for ever and ever. Unlike
> >certain excellent gearmotors we could name :-)
> >
> >Part 5119 - ultra miniature gearmotors (not much more than 1x1x1cm).
> >Never used them, but someone on the list played with some a while back
> >and was quite impressed with the efficiency. NZ$30 each (approx US$16)
> >Part 5278 - chain links x35 (ie miniature caterpillar tracks, about 5mm
> >wide) very close to that MIT "Ant" look.. NZ$9.50 (approx US$5). You
> >might need two sets if your tracks are long.
> >Part 5229 - Assorted gears that mesh with the above tracks. Add a paper
> >hubcap, spray-paint them silver or black, and no-one will ever know
> >you're using lego :-) Additional bonus - they slot right onto the
> >gearmotors. NZ$11.50 (approx US$6)
> >
> >Costly, but I figure this is more than offset by the construction hours
> >saved. (And that MIT "Ant" look is pretty cool :-)



11862 Tue, 14 Mar 2000 23:32:13 -0700 [alt-beam] Re: Photodiodes beam@sgiblab.sgi.com Dave Hrynkiw At 09:29 PM 3/14/00 , Daniel Grace wrote:
>I feel horrible mailing the list so much, but from
>what can photodiodes be salvaged from?

Lessee... the Remote detection modules from VCR's and TV's comes to mind.
Anything you point a remote control at will most likely have a photodiode
as the central receiving element.

Garage door interrupter beam receivers? (Guessing - may use photoresistors)

1/2 of a photointerrupter pair, which is a little "U" shaped module that
has an emitter on one side, and a receiver on the other (which may also be
a phototransistor). Snip it in two and use the receiver. Not sure which is
which? Apply a limited amount of power through it and view it with your
camcorder. The emitter will light up like a flashlight bulb (camcorders are
sensitive to IR). Almost anything electronic will have these. VCR's will
have at least 3 or 4. Camcorders too ;>.

Regards,
Dave

---------------------------------------------------------------
"Um, no - that's H,R,Y,N,K,I,W. No, not K,I,U,U, K,I,_W_. Yes,
that's right. Yes, I know it looks like "HOCKYRINK." Yup, only
2 vowels. Pronounciation? _SMITH_".
http://www.solarbotics.com



11863 Wed, 15 Mar 2000 00:39:08 -0600 [alt-beam] Re: driving muscle wire beam@sgiblab.sgi.com Richard Piotter The thin, weak type is onlt 50 mA. Th larger stuff get's into larger
current values in the hundreds.

David Perry wrote:
>
> thanks for the encouragement :-) Personally i'd be happy with a 4 minute
> stroll - could prove rather expensive though :-) I think its quite
> possible - i think i'll use a a SE to save on weight (and batteries!)- it
> certainly won't be a fast moving critter though. Nitinol doesn't draw too
> much current (50ma) but it ain't too efficient. Should have all the parts
> tomorrow... See what happens. How was nitonol tricky for you?
>
> David
>
> ----- Original Message -----
> From: "Jim Taylor"
> To:
> Sent: Monday, 13 March 2000 11:52
> Subject: Re: driving muscle wire
>
> > ugh muscle wire......how I loved thee......I too tried to biuld a super
> > small walker using nitinol, some SMT parts, some really small lithium
> > batterys, and some really thin music wire. I tried a 4 legger, a 6
> legger,
> > and a tilden worm. The 4 legger showed the most promise, and still does
> > looking back at my work. However Nitinol is very tricky stuff. You mind
> > as well be directly shorting the batterys. Not only do they draw alot of
> > current, but it doesn't transfer very well into torque. It seems (even
> with
> > BORIS, and STIQUITO) no matter how small your driver, and control board
> is,
> > you need alot of battery storage. Unless you like 4 minute strolls :)
> >
> > Don't want to discourge you though.....My mini 4 motor walker walks fine
> on
> > a tether. However I don't think he will do any walking autonomously
> >
> >
> > >
> > >
> > > > To drive a muscle wire you do not even need half of an h-bridge. The
> > > > second transisotr is used to provide a path for current flow. All you
> > > > would need is an NPN transistor with the muscle wire connected between
> > Vcc
> > > > and the collector, the emitter connected to ground and the base
> > connected
> > > > to the input through a resistor. You will want the base resistor small
> > > > enough to drive the transistor into saturation and will probably need
> a
> > > > resistor in series with the muscle wire to control current flow.
> > > > I do not remember off the top of my head, but I think the 50 micron
> > wire
> > > > nominally needs a 100mA current. I do not remember the resistance
> (ohms
> > > > per unit length) off the top of my head. There are a couple sites out
> > > > there with properties on muscle wires (www.dynalloy.com does I am
> sure).
> > I
> > > > would definitely reccomend checking them out because they give other
> > > > helpful hints on using the wires, especially about attaching them.
> > > > I did a concept project a while back using muscle wires for an
> > > > autonomous robot design class. From my experience, which is anything
> but
> > > > all inclusive, I found that the technology is fun and promising but
> > still
> > > > needs some work. You only get about a 5% deformation and the power
> > > > required is still on the high side. I finally settled on a design that
> > > > used four muscle wires for movement of legs down and back (2 frames of
> 3
> > > > legs) and the reverse stroke was handled by a spring system to save on
> > > > power. I was using microprocessor control at the time, never got
> around
> > to
> > > > trying it with BEAM control. If I find time one of these days, I may
> go
> > > > back and finish that... I would be interested to hear what your
> > experience
> > > > with the wire is like. Best of luck.
> > > >
> > > > John Gonser
> > > >
> > > >
> > > > On Tue, 14 Mar 2000, David Perry wrote:
> > > >
> > > > > Okay - haven't asked a question for a while....
> > > > > Okay i'm making a robot, quite advanced, very, very tiny, purely
> > because
> > > i
> > > > > had the idea for it and couldn't get it out of my head all day and
> > it'll
> > > > > drive me mad if i don't build it.
> > > > > The question is - what is the best way to drive muscle wire? You
> would
> > > only
> > > > > use half a hbridge, (no need for switching wires) but i'm thinking
> > thats
> > > > > a little too large. Perhaps a 7hc245 would suffice. I need to drive
> 6
> > > > > pieces of 050 LT, any advice would be appreciated.Oh and why am i
> > using
> > > > > muscle wire? - well i can't find 6x 4mm dia. gearmotors for under
> $31
> > > > > :-)
> > > > >
> > > > > thanks,
> > > > >
> > > > > David
> > > >
> > >
> > >
> >
> >
> > James Taylor
> > "Edgar The Hate Bug"
> > URL: http://fly.to/springmeadows
> > ICQ 14888587
> >
> >

--


Richard Piotter The Richfiles Robotics & TI web page:
richfile@rconnect.com http://richfiles.calc.org

-- Make Money by Simply Surfing the Net or responding to E-Mail!!!
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11864 Wed, 15 Mar 2000 02:16:59 EST [alt-beam] Re: power smart head beam@sgiblab.sgi.com Bumper314@aol.com In a message dated 3/14/00 10:40:46 PM Mountain Standard Time,
sparkyg@seark.net writes:

> there are a few versions..
> do you want the original from Darrell's site?

I was looking for the very original, with just the inverters diagrammed, not
the chip pinout kinda version

Steve



11865 Tuesday, March 14, 2000 4:30 PM Self-Awareness/Conciousness beam@sgiblab.sgi.com Andrew Hooper perhaps if you put in a dark room and slowly moved the light away it might =
move to stay in the light, or have a well lit room with a cardboard box wit=
hg a hole in it. put hole over it so the little light is over the bot then=
slowly move it. try gently pushing the back of its legs. =


Jeremy


>Now I know why my walker is not walking :)
>
>I guess its decided either that this task is to belittling for its
>intelegence
>or that if it walks then it may stumble and fall to its death so its stayi=
ng
>still :)
>
>Hmm, Punishment ... Do i take away your sunlight or hook you to the
>mains :)
>
>Andrew
>
>


content-transfer-encoding: quoted-printable






andrew@best.net.nz>
To:=

href=3D"mailto:beam@sgiblab.sgi.com">beam@sgiblab.sgi.com <
href=3D"mailto:beam@sgiblab.sgi.com">beam@sgiblab.sgi.com>
Date: =

Tuesday, March 14, 2000 4:30 PM
Subject: =

Self-Awareness/Conciousness
 
perhaps if you put in a dark room a=
nd slowly =

moved the light away it might move to stay in the light, or have a well lit=
room =

with a cardboard box withg a hole in it.  put hole over it so the litt=
le =

light is over the bot then slowly move it.  try gently pushing the bac=
k of =

its legs.   

 

Jeremy


 
>Now I know why =
my walker =

is not walking :)
>
>I guess its decided either that this task =
is to =

belittling for its
>intelegence
>or that if it walks then it ma=
y =

stumble and fall to its death so its staying
>still :)
>
>=
;Hmm, =

Punishment ... Do i take away your sunlight or hook you to the
>mains=
=

:)
>
>Andrew
>
>



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